Abstract: In order to improve the dispersion performances of the dispersant applied to the humic acid base coal water mixture, taking the humic acid as the raw m aterial, with the graft copolymerization of the humic acid and with the introduction of the macromolecule hydrophilic long chain, two hydrophilic long chain type dispersa nts of the coal water mixtures were composed and they were the humic acid-sodium allysulfonate-ltaconic acid polyglycol ester ( HSI) and the humic acid-sodium allysul fonate-maleic acid polyglycol ester ( HSMa) .The infrared spectroscopy, thermo gravimetric analysis, differential scanning calorimetry and X-ray diffraction were applied to characterize the two structures of the humic acids. Meanwhile, the apparent viscosity and the rheology of the prepared coal water mixtures were measured. The resul ts showed that the hydrophilicity of the new synthesis dispersant was good, the dispersion performances were excellent, could obviously reduce the apparent viscosity of the coal water mixture and the HSMa performances were better than HSI.